Mastitis treatment

Part II provides detailed information on the main quality and safety issues related to the production of organic livestock foods. This includes three chapters (Chapters 7 to 9) which review the effect of livestock husbandry on nutritional and sensory quality of livestock foods including milk and dairy products (Chapter 7), poultry (Chapter 8) and pork (Chapter 9). It also includes four chapters (Chapters 10 to 13) which review the strategies used to minimise microbiological risks and antibiotic and veterinary medicine use in livestock production systems including safety of ruminants (Chapter 10), mastitis treatment in organic dairy production systems (Chapter 11), internal parasites (Chapter 12) and pigs and poultry (Chapter 13). 

Reducing antibiotic use for mastitis treatment in organic dairy production... 

The objective of mastitis treatments is to cure the infected udders from the infection, but cure is defined in very different ways. For example, in economic terms, the farmer needs to achieve a level of udder health that allows expected milk yields and quality parameters specified by processors/ national regulations to be achieved. On the other hand, cure with respect to antibiotic treatments, is often defined in terms of absence of bacterial pathogens in milk (bacterial cure), with the proportion of cows without detectable pathogen presence following treatment being defined as the bacterial cure rate (BCR). The main problem with using BCR as the main indicator of cure is that it was frequently shown to include a proportion of cows with drastically elevated SCC values (indicative of sub-clinical mastitis) after treatment, but without clinical (sensory) symptoms. 

This cream is suitable for veterinary mastitis treatment. 

There are differences between regulatory authorities in procedures used to set milk withholding periods. USFDA/CVM requires use of at least 20 animals and analysis of milk samples for the marker residue in triplicate.If the product is authorized for mastitis treatment, it is assumed that no more than one-third of the milk is derived from treated cows. A regression line is fitted to the log residue concentration data for each cow, and then fitted lines are used to estimate the distribution of log residue concentrations at each sampling time. Between-animal variance and measurement error variability are estimated and used to calculate a tolerance limit at each time. The WhT is set as the first time at which the upper 95% confidence limit of the 99th percentile of residue concentrations is equal to or less than the MRL. 

Florfenicol (2) has been approved in Japan for the treatment of pseudo-tuberculosis caused by Pasteurellapiscicida and streptococcosis m. yeUowtail fish. The recommended dose is 10 mg/kg for up to one week and the drug withdrawal time is five days after cessation of treatment. Florfenicol is active in bovine respiratory disease caused by Pasteurella species and mastitis caused by Staphylococci and Streptococci. It is also effective in neonatal cohbacillosis caused by E. coli. The drug is being developed worldwide by Schering-Plough Animal Health for the treatment of aquatic and bovine diseases. 

The objective of antibiotic treatments is to reduce the density of microbial pathogen in infected udder tissues and thereby improve the capacity of the animal s immune system to deal with the infection. The effect of a successful antibiotic treatment is therefore self-cure of mastitis (Hamann and Kromker, 1999). However, some antibiotics (e.g. tetracycline and gentamycine) may also have negative side effects on the animal s immune response to udder infection, as they have been shown to inhibit/reduce phagocytosis of the animal s own defence cells (Nickerson et al 1986). 

Given the diversity of disease-causing organisms, the interactions between farm-specific environmental factors and the types of mastitis causing pathogens found, the potential efficacy of antibiotic treatments can only be assessed accurately in the context of the specific on-farm conditions. Furthermore, many recent investigations concluded that, except for some specific infections caused by streptococci, a prophylactic and or longer-term use of antibiotics for chronic and sub-clinical mastitis should not recommended in the future (Deluyker et al., 2005). 

However, in case of acute clinical mastitis, it is widely accepted that animal welfare considerations should take prevalence. If both farmer and veterinarian are not familiar with non-antibiotic treatments, they should be advised to use broad-spectrum antibiotics immediately, because any delay (e.g. the 2-3 days it often takes between diagnosis and the return of microbiological test results) may seriously harm the animal. This approach should, however, only be taken after a sound clinical diagnosis, since antibiotic treatments themselves may lead to dramatic aggravation of the condition. For example, E. coli inflammations are able to develop into severe toxaemia, because increased levels of toxins are released into the animal tissues when E. coli cells are killed or stressed by antibiotic treatments. Also, if yeasts are the main cause or form part of the pathogen complex that causes mastitis, their growth and proliferation may be supported by the administration of anti-bacterial antibiotics (Crawshaw et al., 2005). 

There are reports that the use of robotic milking systems will significantly reduce mastitis, linked at least partially to the machines more efficient teat disinfection compared to human operators. However, the more frequent visit to be milked and more gentle application and removal of milking equipment from the teats may also contribute to reduced mastitis incidence. On the other hand, the absence of human operators in robotically milked herds may lead to late detection and treatment of mastitis. However, this may be overcome by the introduction of conductivity detection systems which allow early signs of mastitis to be detected (Hogeveen and Meijering, 2000). 

Integration of management and treatment approaches farm specific mastitis management plans... 

Crawshaw, W.M., MacDonald, N.R. and Duncan, G. (2005), Outbreak of Candida rugosa mastitis in a dairy herd after intramammary antibiotic treatment . Veterinary Record, 156, 812-813. 

Deluyker, H.A., Chester, S.T. and Van Oye, S.N. (1999), Amultilocation clinical trial in lactating dairy cows affected with clinical mastitis to compare the efficacy of treatment with intramammary infusions of a lincomycin/neomycin combination with an ampicillin/ cloxacillin combination . Journal of Veterinary Pharmacology and Therapy, 22, 274— 282. 

Deluyker H.A., Van Oye, S.N. and Boucher, J.F. (2005). Factors affecting cure and somatic cell count after pirlimycin treatment of subclinical mastitis in lactating cows . Journal of Dairy Science, 88, 604-614... 

Guterbock, W.M., Van Eenennaam, A.L., Anderson, R.J., Gardner, I.A., Cullor, J.S. and Holmberg, C.A. (1993), Efficacy of intramammary antibiotic therapy for treatment of clinical mastitis caused by environmental pathogens . Journal of Dairy Science, 76, 3437-3444. 

Hektoen, L., Larsen, S., Odegaard, S.A. and Loken, T. (2004), Comparison of homeopathy, placebo and antibiotic treatment of clinical mastitis in dairy cows - methodological issues and results from a randomized-clinical trial. Journal of Veterinary Medicine A Physiology, Pathology and Clinical Medicine, 51, 439-446. 

Leininger, D.J., Roberson, J.R., Elvinger, R, Ward, D. and Akers, R.M. (2003), Evaluation of frequent milkout for treatment of cows with experimentally induced Escherichia coli mastitis . Journal of the American Veterinary Medical Association, 222, 63-66. 

Malinowski, E. (2002), The use of some immunomodulators and non-antibiotic drugs in a prophylaxis and treatment of mastitis . Polish Journal of Veterinary Sciences, 5, 197-202. 

Meany, W.J. (1995), Treatment of mastitis with homeopathic remedies . IDF Mastitis Newsletter, 5-6. 

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